A team of MIT and Harvard researchers have successfully converted a laser, which is a bundle of light beams, into a single string of photons, representing a major step forward for quantum computing technology. "Senior author Vladan Vuletić...says the achievement 'could enable new quantum devices' such as quantum gates, where a single photon switches the direction of travel or polarization of another photon. This goal has been very hard to attain, Vuletić explains, because photons ordinarily interact, at best, only very weakly with one another."

What's the Big Idea?

Because quantum computers can, in theory, perform parallel operations (unlike contemporary chip-based computers which use linear logic), they could function more similarly to the human mind, solving complex computations much faster than today's machines. And because of the laws governing quantum operations, if a quantum computer were used for communication, it would be entirely immune from eavesdropping. "This work is an exciting new development in this direction," said Eugene S. Polzik, professor of physics at the Niels Bohr Institute at Copenhagen University and director of the Danish Center for Quantum Optics. "It paves the way towards new implementations of photon quantum logic."

Even the optimists among us would have to admit 2018 was a challenging year. The fractured world that became the focus of our 2018 Annual Meeting a year ago came under further pressure from populist rhetoric and rising nationalist agendas. At the same time, the urgent need for coordinated global action in areas such as climate change, inequality and the impact of automation on jobs became more intense.